Coordination of (β-N-sulfonylaminoalkyl)phosphines and their analogous arsines to PdII and PtII. Application of the Pd-complexes as chiral catalysts in asymmetric hydrosilylation of 1,3-dienes

Abstract

Optically active ligands 2 and 3 were synthesised from phenylglycine and the coordination of ligand 2 to PdCl₂(CH₃CN)₂ and PtCl₂(C₆H₅CN)₂ was studied with ¹H, ³¹P and ¹⁵N–¹H-HMQC NMR spectroscopy. The results indicated P,O rather than P,N bidentate coordination. Both ligands were tested in the palladium catalysed hydrosilylation of cyclic 1,3-dienes. Asymmetric induction of up to 84% (≤25% yield), which is the hitherto highest reported ee value for asymmetric hydrosilylation of 1,3-dienes, was achieved as measured on the allylic alcohols formed after ethanolysis–oxidation of the initially formed allylic silanes.